PMID- 8068028
OWN - NLM
STAT- MEDLINE
DCOM- 19940921
LR  - 20191210
IS  - 0264-6021 (Print)
IS  - 1470-8728 (Electronic)
IS  - 0264-6021 (Linking)
VI  - 302 ( Pt 1)
IP  - Pt 1
DP  - 1994 Aug 15
TI  - Cytosolic calcium pre-elevation amplifies agonist-induced calcium release in 
      human leukaemic HL-60 cells.
PG  - 87-94
AB  - Histamine, ATP, and two microsomal Ca(2+)-pump inhibitors, thapsigargin (TG) and 
      cyclopiazonic acid (CPA), were able to release intracellular Ca2+ in human 
      leukaemic HL-60 cells. The relationships between the agonist-, TG- and 
      CPA-sensitive Ca2+ pools were investigated with optimal concentrations of these 
      agents in Ca(2+)-free medium. CPA failed to release Ca2+ after the Ca2+ stores of 
      the cells had been discharged by TG, and vice versa, suggesting that the TG- and 
      CPA-sensitive pools exactly overlap. Using this protocol, it was further 
      demonstrated that (a) histamine and ATP utilized the same agonist-sensitive pool, 
      and (b) the CPA- or TG-sensitive pool was much larger than, and encompassed, the 
      agonist-sensitive pool. Although optimal (30 microM) CPA treatment for 5 min 
      totally emptied the agonist-sensitive pool, a brief exposure (1.5 min) to a 
      sub-optimal concentration (3 microM) of CPA, which only slightly raised cytosolic 
      free Ca2+ concentration ([Ca2+]i), substantially enhanced subsequent 
      agonist-induced Ca2+ release. Brief pretreatments with sub-optimal concentrations 
      of TG or ionomycin, which caused moderate [Ca2+]i elevation, also caused such 
      enhancement. However, sub-optimal CPA pretreatment had no prominent effect on 
      Ca2+ release, which was InsP3-independent: it did not enhance TG-induced Ca2+ 
      release, and only relatively weakly augmented ionomycin-induced Ca2+ release. Our 
      results represent a novel observation showing that low concentrations of CPA, TG 
      and ionomycin can potentiate subsequent agonist-induced Ca2+ release, and suggest 
      that a 'priming' moderate [Ca2+]i elevation can amplify subsequent 
      InsP3-dependent Ca2+ release in HL-60 cells.
FAU - Leung, Y M
AU  - Leung YM
AD  - Department of Physiology, Faculty of Medicine, University of Hong Kong.
FAU - Kwan, C Y
AU  - Kwan CY
FAU - Loh, T T
AU  - Loh TT
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Biochem J
JT  - The Biochemical journal
JID - 2984726R
RN  - 0 (Indoles)
RN  - 0 (Terpenes)
RN  - 56092-81-0 (Ionomycin)
RN  - 67526-95-8 (Thapsigargin)
RN  - 820484N8I3 (Histamine)
RN  - 85166-31-0 (Inositol 1,4,5-Trisphosphate)
RN  - 8L70Q75FXE (Adenosine Triphosphate)
RN  - EC 7.2.2.10 (Calcium-Transporting ATPases)
RN  - SY7Q814VUP (Calcium)
RN  - X9TLY4580Z (cyclopiazonic acid)
SB  - IM
MH  - Adenosine Triphosphate/pharmacology
MH  - Calcium/*metabolism
MH  - Calcium-Transporting ATPases/antagonists & inhibitors/metabolism
MH  - Cytosol/*metabolism
MH  - Histamine/pharmacology
MH  - Humans
MH  - Indoles/pharmacology
MH  - Inositol 1,4,5-Trisphosphate/metabolism
MH  - Ionomycin/pharmacology
MH  - Leukemia
MH  - Terpenes/pharmacology
MH  - Thapsigargin
MH  - Tumor Cells, Cultured
PMC - PMC1137194
EDAT- 1994/08/15 00:00
MHDA- 1994/08/15 00:01
PMCR- 1994/08/15
CRDT- 1994/08/15 00:00
PHST- 1994/08/15 00:00 [pubmed]
PHST- 1994/08/15 00:01 [medline]
PHST- 1994/08/15 00:00 [entrez]
PHST- 1994/08/15 00:00 [pmc-release]
AID - 10.1042/bj3020087 [doi]
PST - ppublish
SO  - Biochem J. 1994 Aug 15;302 ( Pt 1)(Pt 1):87-94. doi: 10.1042/bj3020087.